After the Suns beat San Antonio in Game 4 to tie the series 2-2, Duncan calmly said the Spurs would win Game 5 at home, then return to Phoenix and finish the series in Game 6.

The Spurs, the No. 1 seed in the West after an NBA-best 60-win regular season, lead the best-of-seven series 3-2 after winning at home 94-82 on Tuesday night.

San Antonio can validate Duncan's proclamation and eliminate the pesky Suns with a victory Thursday night at America West Arena.

Fulfilling Johnson's guarantee will be more difficult because of the nerve injury to Stephon Marbury's right shoulder.

Marbury's fingers were still numb from the injury after Wednesday's practice, but he vowed to give it his best shot as the Suns try to force a deciding Game 7.

"I wouldn't miss this game for the world," he said. "This is definitely the biggest game of my career."

Marbury, who scored a series-low 13 points on 5-for-18 shooting in Game 5, tried to shrug off the injury but acknowledged it has bothered him.

"I wasn't all right yesterday," he said. "Dribbling, everything _ I just wasn't myself. But with a day of rest, with stretching and exercising, I'm a lot better than I was yesterday."

The numbness in his hand remained, however.

"If anybody ever hit their funnybone in their arm, they pretty much know how that feels," Marbury said. "For me, that's like constant. Your fingers go numb. If I get hit, I feel a sharp pain, then it will go away in about 30 seconds, but I still have that dull pain in my hand."

He said he will know his limitations.

"I just play the way the game is supposed to be played," Marbury said. "I'm not going to try to go out and do something I can't do. But just my presence on the basketball court, I think, will help my team."

If Marbury can't be his usual scoring threat, that will put more of an offensive burden on Shawn Marion, Penny Hardaway and Amare Stoudemire, who have been inconsistent in the series.

"If his arm isn't right, then guys on the team are going to be saying `We'll take it and pick up the slack,'" Hardaway said. "I'm going to be ready."

The Suns plan to keep up the full-court pressure that allowed them to make a serious dent in San Antonio's 24-point halftime lead Tuesday night.

"We've just got to keep fresh bodies in there and keep rotating," Johnson said.

Turnovers against the Suns' pressure have been a big problem for the Spurs.

"It's something we need to stay away from," Duncan said. "They get in the open court, they're very athletic. They get that energy and get going."

The Spurs did not practice before flying to Phoenix on Wednesday. After Game 5, they were a bit perturbed about allowing the Suns to get back into it in the second half and thereby take some positive feelings into Game 6.

"It's still frustrating in that situation to start turning the ball over and they get back into the game," Duncan said after Tuesday's game.